deriving...

[MR K P SCHUPKE]

> * I'm not at all keen on making '..deriving( Foo )' mean
>   $(derive 'Foo) or something like that.  Just make the TH
>   call yourself!

The current situation is that the code that generates the derived 
instances is hard coded into the compiler (TcDeriv.hs) is it not
better to allow the derived instances to be specified in Haskell
- using template-haskell seems to be the easiest (least new
features/least effort/max results) method of doing this. What
I am suggesting is that the current derivations for Typeable
(etc) are replaced by more readable template-haskell code, that
can be user extended... Surely it is better to have the deriving
method exposed rather than hidden away in the compiler. 

	Keean.